Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011881 (diabetic nephropathy)
 10,836 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

SR121463 is a selective, orally active, non-peptide antagonist of vasopressin (AVP) V(2) receptors with powerful aquaretic properties in various animal species and humans. SR121463 belongs to a new class of drugs, called aquaretics, which are capable of inducing free-water excretion without affecting electrolyte balance. SR121463 displays high affinity for animal and human V(2) receptors and exhibits a remarkably selective V(2) receptor profile. SR121463 and [(3)H]SR121463 are used, therefore, as selective probes for characterization and labeling of V(2) receptors. In various functional studies in vitro, SR121463 behaves as a potent antagonist. It inhibits AVP-stimulated human renal adenylyl cyclase and dDAVP (1-desamino, 8-D arginine-vasopressin)-induced relaxation of rat aorta. SR121463 also behaves as an inverse agonist in cells expressing a constitutively activated human V(2) receptor mutant. In vitro, SR121463 rescued misfolded V(2) AVP receptor mutants by increasing cell surface expression and restoring V(2) function. In normally hydrated conscious rats, dogs and monkeys, SR121463, by either i.v. or p.o. administration, induced a dose-dependent aquaresis with no major changes in urinary Na+ and K+ excretion (unlike classical diuretics). In cirrhotic rats with ascites and impaired renal function, a 10-day treatment with SR121463 totally corrected hyponatremia and restored normal urine excretion. In a model of diabetic nephropathy in rats, SR121463 strongly reduced albumin excretion. SR121463 was also effective at extrarenal V(2) (or V(2)-like) receptors involved in vascular relaxation or clotting factor release in vitro and in vivo. In the rabbit model of ocular hypertension, SR121463 by either single or repeated instillation, decreased intraocular pressure. After acute and chronic administration to rats, dogs or healthy human volunteers, SR121463 was well absorbed and well tolerated. In all species studied the drug produced pronounced aquaresis without any agonist effect. Thus, SR121463 is a potent, orally active and selective antagonist at V(2) receptors with powerful aquaretic properties. It is a useful tool for further exploration of function of renal or extrarenal V(2) receptors. Pure V(2) receptor antagonists are likely to be therapeutically useful in several water-retaining diseases such as hyponatremia, Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH), congestive heart failure, liver cirrhosis, and other disorders possibly mediated by V(2) receptors (e.g., glaucoma).
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PMID:An overview of SR121463, a selective non-peptide vasopressin V(2) receptor antagonist. 1160 38

Uruguay is a developing country with 3.16 million inhabitants. Chronic dialysis treatment (CDT) expanded after the creation of a National Fund of Resources in 1980 who receives contribution from all inhabitants to finance, among others, the CDT and renal transplantation. During the 1981-1998 period, about 4,819 patients were treatment, 2,365 patients had died, 454 were transplanted and 51 patients were lost to follow-up due to change in residence. At the start of the treatment, mean age was 57.0 +/- 17.7 years, 37% were 65 or older than 65 year old, 61.3% were male and 98% of patients were white persons. The most common diseases responsible for End Stage Renal Disease were: hypertension (22%), chronic glomerulonephritis (19%) and diabetic nephropathy (15%). In 1998, there were 44 dialysis units in the country (13.6 units per million population--pmp), 100% of them had water treatment (reverse osmosis 96.8%) and reuse dialyzer. The most frequent causes of death were: cardiovascular and infection. In this paper, eighteen years of the mortality time course of CDT are analyzed. Annual mortality rate was expressed as deaths per 1,000 patients years at risk (M/1,000). The indirect standardization method was applied to adjust the mortality rate. Two populations were used as standard: the 1996 population of USRDS to adjust for age, sex, race and nephropathy and the 1996 Uruguayan general population to adjust for age. Standardized mortality rate (SMR) for each year was obtained dividing observed deaths by expected deaths. From 1981 to 1998, the incident population increased from 32 to 133 patients per million populations and the prevalent population from 28 to 639 pmp. There was a simultaneously increase in the prevalence of diabetic patients and of patients older than 65 years. The annual mortality rate decreased from 249 to 138 deaths per 1,000 patient years (M/1,000). The standardized mortality (SM) with the USRDS population as standard decreased from 452 in 1981 to 132 in 1998 and the SMR from 2.07 to 0.60. The SMR with the Uruguayan general population decreased from 17 to 4. In conclusion, these results are similar with those observed in developed countries. There has been a decrease both in the gross and the standardized mortality ratio in the period of observation.
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PMID:[Chronic dialysis in Uruguay: mortality trends from 1981 to 1998]]. 1181 9

Hyperhomocysteinemia is known to be associated with many of the occlusive vascular diseases including ischemic heart disease. Elevated plasma total homocysteine (t-Hcy) is also remarkably common among patients with moderate to severe renal failure. The purpose of this study was to investigate the role of homocysteine (Hcy) in the pathogenesis of diabetic nephropathy in the rat. Additionally, any effect of aminoguanidine (AG), an inhibitor of advanced glycation end product (AGE) formation, on the onset of nephropathic symptoms and on the concentrations of Hcy was searched for. Diabetes was induced in male Wistar albino rats (6 months old) by a single injection of 50 mg x kg (-1)streptozotocin (STZ) into the penile vein. Animals with blood glucose levels higher than 350 mg x dl (-1)72 h after STZ injection were included in the study. Age-matched rats receiving a single dose of citrate buffer served as controls. One half of the control and diabetic groups received AG via drinking water (1 g l (-1)). The experimental period lasted for ten weeks. Animals were killed by cardiac venipuncture after 24 hour urine samples were collected. Serum t-Hcy was quantified using HPLC, and urinary GAGs using the spectrophotometric 1,9-dimethyl methylene blue dye method. Serum glucose, protein, creatinine and total sulfydryl (t-SH) measurements, and urinary protein determinations were carried out spectrophotometrically. In diabetic rats, serum t-Hcy levels were significantly decreased (P< 0.001), and were negatively correlated with the urinary protein concentration (r= -0.67, P< 0.05). Urinary GAG levels were also increased in diabetic rats (P< 0.001). AG neither affected the t-Hcy levels, nor ameliorated the nephropathic symptoms. These results indicate that diabetic nephropathy is not linked to homocysteinemia in the rat.
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PMID:A study on the relationship between homocysteine and diabetic nephropathy in rats. 1188 23

Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors. Three PPAR isoforms, designated PPAR-alpha, beta/delta and -gamma, have been identified and were initially investigated in the tissues along urinary tract because of their known role in regulating lipid-activated gene transcription, lipid metabolism, inflammation and cell proliferation and differentiation. Gene distribution studies suggested that 3 PPAR isoforms are differentially expressed in the kidney. PPAR-alpha is predominantly expressed in renal proximal tubules and medullary thick ascending limbs. PPAR-gamma is mainly localized in renal medullary collecting duct with lower expression in renal glomeruli and renal microvasculature. Unlike PPAR-alpha and -gamma, PPAR-beta/delta is ubiquitously expressed in every segment along the nephron. In ureter and urinary bladder, all PPAR isoforms are mainly localized in urothelium of ureter and bladder. The emerging data have suggested physiological and pathophysiological roles of PPARs in tissues along urinary tract. PPAR-alpha plays a major role in triggering fatty acid utilization and the adaptive response to dietary lipids in the kidney. PPAR-beta/delta contributes to cell survival of renal interstitial cell in medullary hyperosmality. PPAR-gamma is involved in regulating renal hemodynamic and water and sodium transport. Furthermore, it also participates in the pathogenesis of glomerulopathy, antidiabetic thiazolidinedione-related water and sodium retention and renal, bladder and prostate carcinomas. PPARs may serve as potential therapeutic targets for certain diseases along urinary tract including glomerulosclerosis, diabetic nephropathy and kidney, prostate and bladder tumors.
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PMID:Targeting peroxisome proliferator-activated receptors (PPARs) in kidney and urologic disease. 1218 90

Aquaporin-2 (AQP-2) is known to be expressed in the renal collecting duct cells and participates in urinary concentration in response to arginine vasopressin (AVP). The present study was undertaken to determine whether progression of renal dysfunction affects urinary excretion of AQP-2 in diabetic nephropathy. The study was composed of 8 control subjects and 14 patients with type 2 diabetes classified into two groups according to serum creatinine level (cut-off point; 1.5 mg/dl). After an 8-hour water deprivation, both urinary osmolality (U(osm)) and urinary excretion of AQP-2 significantly decreased in the diabetic patients with chronic renal failure as compared to the control subjects (p < 0.0001, p < 0.05, respectively). After a water load (10 ml/kg), no differences were found in plasma osmolality (P(osm)), AVP levels and U(osm), whereas urinary excretion of AQP-2 significantly decreased in the patients with chronic renal failure as compared to the control subjects (p < 0.05). These results indicate that the decreased urinary excretion of AQP-2 in diabetic nephropathy is due to the impaired cellular signaling of AVP in collecting duct cells, which may be partly involved in the urinary concentrating defect in renal failure.
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PMID:Decrease in urinary excretion of aquaporin-2 associated with impaired urinary concentrating ability in diabetic nephropathy. 1221 27

It appears to be confirmed by international studies that the development of end-stage nephropathy, cardiovascular mortality and morbidity can be reduced to a large extent by achieving a target blood pressure of 130/85 mmHg in diabetes hypertension and 125/75 mmHg in diabetic nephropathy. Diuretics, beta-blockers, ACE inhibitors and calcium antagonists are all recommended agents with evidence "A" according to both international and national recommendations. The most efficient nephroprotection and simultaneous intensive and efficient blood pressure reduction can be achieved by ACE inhibitors and AT1 receptor blockers as basic agents. It is often required to use combination treatment to achieve the target blood pressure. In the predialysis stage, tight blood pressure control should be completed with balanced glucose metabolism, restricted protein intake, controlled salt and water metabolism, early treatment of metabolic acidosis and preparation for kidney substitution treatment. The patient and the treating physicians should work together in a coordinated way during the complex nephrology, diabetes, cardiology care to slow down the progress of the disease.
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PMID:[Therapy of diabetic nephropathy]. 1262 14

The renin-angiotensin-aldosterone system (RAAS) exerts a principal influence in maintaining vascular tone, optimal salt and water homeostasis, and forward cardiac output in human beings. Overactivity of the RAAS can lead to pathologic consequences in states of diabetic nephropathy, hypertension, renal artery stenosis, left ventricular hypertrophy, coronary atherosclerosis, myocardial infarction, and congestive heart failure. In addition to fluid and hemodynamic effects, the RAAS may have a critical role in the activation of the sympathetic nervous system, the progression of atherosclerosis, the dysregulation of endothelial function, and the inhibition of the fibrinolytic system. Accumulated basic and clinical evidence supports the use of inhibitors of the RAAS, including aldosterone antagonists, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers, in treating hypertension, improving diabetic nephropathy, preventing or ameliorating congestive heart failure, and optimizing the prognosis after myocardial infarction.
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PMID:Renin-angiotensin-aldosterone system: fundamental aspects and clinical implications in renal and cardiovascular disorders. 1267 84

The renin-angiotensin-aldosterone system (RAAS) plays an integral role in maintaining vascular tone, optimal salt and water homeostasis, and cardiac function in humans. However, it has been recognized in recent years that pathologic consequences may also result from overactivity of the RAAS. Clinical disease states such as renal artery stenosis, hypertension, diabetic and nondiabetic nephropathies, left ventricular hypertrophy, coronary atherosclerosis, myocardial infarction, and congestive heart failure (CHF) are examples. Part of the adverse cardiorenal effects of the RAAS may be related to the prominent role that this system plays in the activation of the sympathetic nervous system, the dysregulation of endothelial function and progression of atherosclerosis, as well as inhibition of the fibrinolytic system. Also, direct profibrotic actions of angiotensin II and aldosterone in the kidney and heart promote end organ injury. Current basic science and clinical research supports the use of inhibitors of the RAAS, including angiotensin converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone antagonists in treating hypertension, improving diabetic nephropathy and other forms of chronic kidney disease, preventing or ameliorating CHF, and optimizing prognosis after myocardial infarction.
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PMID:The renin-angiotensin-aldosterone system: cardiorenal effects and implications for renal and cardiovascular disease states. 1286 Nov 21

Water balance depends essentially on fluid intake and urine excretion. Mild dehydration and the consequent hypertonicity of the extracellular fluid induce an increase in vasopressin secretion, thus stimulating urine concentrating processes and the feeling of thirst. The osmotic threshold for the release of vasopressin is lower than that for thirst and also shows appreciable individual variation. Sustained high levels of vasopressin and low hydration induce morphological and functional changes in the kidney. However, they could also be risk factors in several renal disorders, such as chronic renal failure, diabetic nephropathy and salt-sensitive hypertension.
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PMID:Mild dehydration, vasopressin and the kidney: animal and human studies. 1468 12

The aim of this study was to analyze the effect of vitamins C and E on malondialdehyde (MDA) content and activities of key antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) as well as glomerular basement membrane (GBM) thickness in streptozotocin-induced diabetic kidney in rats. Wistar male rats were divided into following groups (12 rats each): the control, diabetic rats, diabetic rats whose drinking water was supplemented with vitamin C in a dose of 1.0 g/l or diet was supplemented with 200 mg of vitamin E/100 g fodder. Body weight, blood glucose and HbA1C levels and 24-hour urinary albumin excretion (UAE) were studied every week (0-12 weeks). After 6 and 12 weeks, MDA content and activities of SOD, CAT and GSH-Px were measured in the kidney homogenate supernatants. Electron micrographs of glomeruli were scanned and morphometric investigations were performed by means of computer image analysis system to compare GBM thickness. The blood glucose and HbA1C concentrations and UAE in diabetic rats were significantly higher than in the control group. An increase in the MDA level and decrease in the SOD, CAT and GSH-Px activities in the kidney of diabetic rats were observed after 6 and 12 weeks of experiment. Administration of vitamins C and E did not affect body weight, blood glucose and HbA1C levels. Both vitamin C and vitamin E decreased lipid peroxidation and augmented the activities of antioxidant enzymes studied in the kidneys of diabetic rats as well as reduced UAE, decreased kidney weight and GBM thickness. The results indicate the potential utility of antioxidant vitamins in the protection against the development of diabetic nephropathy.
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PMID:Effect of vitamin E and vitamin C supplementation on antioxidative state and renal glomerular basement membrane thickness in diabetic kidney. 1469 67


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